Carrier aggregation using split band filters

ABSTRACT

Improved switched multiplexer architecture for supporting carrier aggregation in front-end applications. Front end architectures are disclosed that use two filters for a particular frequency band to allow for carrier aggregation using bands that at least partially overlap in frequency. An antenna switch module can be used to independently couple individual filters to an antenna to support a variety of carrier aggregation modes. Switches that connect to the two filters that split the particular frequency band can be configured to operate independently so as to only pass signals within a sub-band of the particular frequency band when operating in certain carrier aggregation modes.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.16/197,339 filed Nov. 20, 2018 and entitled “METHODS FOR PROVIDINGCARRIER AGGREGATION,” which is a continuation of U.S. application Ser.No. 15/484,045 filed Apr. 10, 2017 and entitled “UPLINK AND DOWNLINKCARRIER AGGREGATION,” which is a continuation of U.S. application Ser.No. 14/487,004 filed Sep. 15, 2014 and entitled “SYSTEMS AND METHODSRELATED TO CARRIER AGGREGATION FRONT-END MODULE APPLICATIONS,” whichclaims priority to U.S. Prov. App. No. 61/879,128 filed Sep. 17, 2013and entitled “IMPROVED SWITCHED MULTIPLEXER ARCHITECTURE TO SUPPORTCARRIER AGGREGATION FRONT END MODULE APPLICATIONS,” and to U.S. Prov.App. No. 61/929,961 filed Jan. 21, 2013 and entitled “SYSTEMS ANDMETHODS RELATED TO CARRIER AGGREGATION FRONT-END MODULE APPLICATIONS,”the disclosure of each of which is hereby expressly incorporated byreference herein in its respective entirety for all purposes.

BACKGROUND Field

The present disclosure relates to systems and methods for carrieraggregation in front-end module applications.

Description of the Related Art

Many designs for wireless devices such as smartphones and tablets desirelower cost and smaller size, while simultaneously increasing complexityand performance requirements. Radio-frequency (RF) front-end modules(FEMs) provide a platform where at least some of such designs can beimplemented. For example, functionalities associated with switching,filtering, and power amplifiers (PAs) can be implemented in a FEM.

SUMMARY

In accordance with some implementations, the present disclosure relatesto an N-plexing system that includes an assembly of filters configuredto provide N filtered paths, and a switching circuit in communicationwith the assembly of filters. The switching circuit is configured toprovide a plurality of switchable paths between the assembly of filtersand an antenna port to allow simultaneous operation between the Nfiltered paths and the antenna port.

In some embodiments, N can be equal to 4 such that the N-plexing systemis a quadruplexing system. In some embodiments, the assembly of filterscan include a first duplexer and a second duplexer, with each duplexerbeing configured to provide two filtered paths. In some embodiments, theassembly of filters can include a duplexer and two individual filters,with the duplexer being configured to provide two filtered paths, andeach individual filter being configured to provide one filtered path. Insome embodiments, the assembly of filters can include four individualfilters, with each individual filter being configured to provide onefiltered path.

In some embodiments, N can be equal to 2 such that the N-plexing systemis a duplexing system. The assembly of filters can include twoindividual filters, with each individual filter being configured toprovide one filtered path.

In some embodiments, the N-plexing system can further include aplurality of signal conditioning circuits implemented between theassembly of filters and the switching circuit. In some embodiments, atleast some of the signal conditioning circuits can include an impedancematching circuit. In some embodiments, at least some of the signalconditioning circuits can include a filter configured to reject aharmonic component. Such a filter can be configured as a notch filter,and the harmonic component can include a second harmonic.

In some embodiments, at least some of the signal conditioning circuitscan include a phase shifting circuit. Such a phase shifting circuit canbe configured to include tunable shifting of phase.

In a number of implementations, the present disclosure relates to amethod for operating a wireless device. The method includes enablingsimultaneous operation of N filtered signals. The method furtherincludes performing one or more switching operations to provide aplurality of switched paths for the N filtered signals to and from anantenna.

In some implementations, the present disclosure relates to a switchmodule that includes a packaging substrate configured to receive aplurality of components, and a switching circuit implemented on thepackaging substrate. The switching circuit includes a plurality ofswitchable paths between an antenna port and respective filter nodes.The plurality of switchable paths is configured to be operated togetherto allow simultaneous operation between the antenna port and N filteredpaths coupled to the filter nodes.

In a number of teachings, the present disclosure relates to a front-endmodule (FEM) that includes a filter circuit configured to provide Nfiltered paths, with each filtered path including a node capable ofbeing coupled to a receiver circuit or a transmitter circuit. The FEMfurther includes a switching circuit in communication with the filter.The switching circuit is configured to provide a plurality of switchablepaths between the filter circuit and an antenna port to allowsimultaneous operation between the N filtered paths and the antennaport.

In some embodiments, the switching circuit can be implemented on anantenna switching module (ASM). In some embodiments, the switchingcircuit can be implemented on a semiconductor die. In some embodiments,at least some of the filter circuit can be implemented on thesemiconductor die.

According to some implementations, the present disclosure relates to aradio-frequency (RF) device that includes a transceiver configured toprocess RF signals, and a front-end module (FEM) in communication withthe transceiver. The FEM includes a filter circuit configured to provideN filtered paths, with each filtered path including a node capable ofbeing coupled to a receiver circuit or a transmitter circuit. The FEMfurther includes a switching circuit in communication with the filter.The switching circuit is configured to provide a plurality of switchablepaths between the filter circuit and an antenna port to allowsimultaneous operation between the N filtered paths and the antennaport. The RF device further includes an antenna in communication withthe antenna port. In some embodiments, the RF device can include awireless device such as a cellular phone.

In some implementations, the present disclosure relates to a switchingcircuit having a first switch between a B1 duplexer and an antenna port,and a second switch between a B7 duplexer and the antenna port.

In some implementations, the present disclosure relates to a switchingcircuit having a first switch between a B2 duplexer and an antenna port,and a second switch between a B4 duplexer and the antenna port.

In some implementations, the present disclosure relates to a switchingcircuit having a first switch between a B5 duplexer and an antenna port,and a second switch between a B12 duplexer and the antenna port.

In some implementations, the present disclosure relates to a switchingcircuit having a first switch between a B8 duplexer and an antenna port,and a second switch between a B17 or B20 duplexer and the antenna port.

In some implementations, the present disclosure relates to aradio-frequency (RF) circuit that includes an assembly of filtersconfigured to provide duplexer capability for each of a plurality ofbands. The assembly of filters includes an aggregated filter configuredto filter a first RF signal associated with a first band and a second RFsignal associated with a second band different than the first band. TheRF circuit further includes a switching circuit in communication withthe assembly of filters and an antenna port. The switching circuitincludes a switchable path in communication with the aggregated filterand the antenna port. The switchable path is configured to facilitatepassage of the first RF signal and the second RF signal through theaggregated filter.

In some embodiments, the switching circuit can further include a bandselection switch in communication with the switchable path and theantenna port, with the switching circuit being configured to select aduplex signal path for each of the plurality of bands. In someembodiments, the RF circuit can further include an assembly of phasedelay components, with the assembly of phase delay components beingconfigured to facilitate aggregation of RF signal paths resulting fromoperation of the aggregated filter.

In some embodiments, the switchable circuit can include a field-effecttransistor (FET) switch. The FET switch can include asilicon-on-insulator (SOI) FET.

In some embodiments, at least some portions of the first band and thesecond band can overlap. The plurality of bands can include, forexample, B1, B3 and B4, with B1 having a transmit (TX) frequency rangeof 1920 to 1980 MHz and a receive (RX) frequency range of 2110 to 2170MHz, B3 having a TX frequency range of 1710 to 1785 MHz and an RXfrequency range of 1805 to 1880 MHz, and B4 having a TX frequency rangeof 1710 to 1755 MHz and an RX frequency range of 2110 to 2155 MHz. Theaggregated filter can be configured to aggregate B1 RX and B4 RX bands.The aggregated filter can be configured to aggregate B3 TX and B4 TXbands. In some embodiments, the plurality of bands can further includeB2 having a TX frequency range of 1850 to 1910 MHz and an RX frequencyrange of 1930 to 1990 MHz.

According to a number of implementations, the present disclosure relatesto a radio-frequency (RF) module that includes a packaging substrateconfigured to receive a plurality of components, and an assembly offilters implemented on the packaging substrate. The assembly of filtersis configured to provide duplexer capability for each of a plurality ofbands. The assembly of filters includes an aggregated filter configuredto filter a first RF signal associated with a first band and a second RFsignal associated with a second band different than the first band. TheRF module further includes an antenna switching module (ASM) implementedon the packaging module. The ASM is in communication with the assemblyof filters and an antenna port. The ASM includes a switchable path incommunication with the aggregated filter and the antenna port. Theswitchable path is configured to facilitate passage of the first RFsignal and the second RF signal through the aggregated filter.

In some embodiments, the RF module can be a front-end module (FEM). TheFEM can further include a power amplifier module (PAM) having aplurality of power amplifiers.

According to some implementations, the present disclosure relates to aradio-frequency (RF) device that includes a transceiver configured toprocess RF signals, and a front-end module (FEM) in communication withthe transceiver. The FEM includes an assembly of filters configured toprovide duplexer capability for each of a plurality of bands. Theassembly of filters includes an aggregated filter configured to filter afirst RF signal associated with a first band and a second RF signalassociated with a second band different than the first band. The FEMfurther includes an antenna switching module (ASM) in communication withthe assembly of filters and an antenna port. The ASM includes aswitchable path in communication with the aggregated filter and theantenna port. The switchable path is configured to facilitate passage ofthe first RF signal and the second RF signal through the aggregatedfilter. The RF device further includes an antenna in communication withthe antenna port. The antenna is configured to facilitate either or bothof transmission and receiving of RF signals. In some embodiments, RFdevice can include a wireless device such as a cellular phone.

For purposes of summarizing the disclosure, certain aspects, advantagesand novel features of the inventions have been described herein. It isto be understood that not necessarily all such advantages may beachieved in accordance with any particular embodiment of the invention.Thus, the invention may be embodied or carried out in a manner thatachieves or optimizes one advantage or group of advantages as taughtherein without necessarily achieving other advantages as may be taughtor suggested herein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 schematically depicts a carrier-aggregation architecture havingone or more features as described herein.

FIG. 2 show an example of a front-end module (FEM) architecture thatutilizes a conventional implementation of B1, B3 and B4 bands.

FIG. 3 shows an example where some or all of circuits and relatedcomponents associated with a B4 duplexer can be removed.

FIG. 4 shows an example where a carrier aggregation configuration can beimplemented to address 4G systems.

FIG. 5 shows an example where a carrier aggregation configuration suchas the example of FIG. 4 can be modified to accommodate more complexdesigns.

FIG. 6 shows an example of a FEM that utilizes a traditional duplexerand quadruplexer design to support LTE carrier aggregation.

FIG. 7 shows an example of a FEM that utilizes a design having one ormore features as described herein to, among others, support LTE carrieraggregation.

FIG. 8 shows another example of a FEM that utilizes a design having oneor more features as described herein to, among others, support LTEcarrier aggregation.

FIG. 9 shows an example of a switched multiplexing configuration forsupporting LTE carrier aggregation for B25+B4, B1+B7 and B3+B7.

FIG. 10 shows an example of a switched multiplexing configuration thatcan address a harmonic problem.

FIG. 11 shows an example switched-in filter configuration that includesa duplexer coupled to its corresponding switch on an antenna switchmodule (ASM) through a fixed phase shifting circuit and a tunable phaseshifting circuit.

FIG. 12 shows that in some embodiments, one or more features of thepresent disclosure can be implemented in a FEM for a radio-frequency(RF) device such as a wireless device.

FIG. 13 schematically depicts an example wireless device having one ormore advantageous features described herein.

DETAILED DESCRIPTION OF SOME EMBODIMENTS

The headings provided herein, if any, are for convenience only and donot necessarily affect the scope or meaning of the claimed invention.

FIG. 1 schematically depicts a carrier-aggregation architecture 100having one or more features as described herein. In some embodiments,such an architecture can include an assembly of filters 102 and aswitching circuit 106 configured to provide duplexing or multiplexingfunctionalities for radio-frequency (RF) signals to be transmitted(RF_TX) and received RF signals (RF_RX). Such RF signals can betransmitted and received through one or more antennas. Suchduplexing/multiplexing functionalities can be provided for differentbands associated with wireless devices.

FIG. 1 further shows that in some embodiments, at least one filter inthe assembly of filters 102 can be an aggregated filter 104 configuredto provide filtering functionality for two or more different bands. Asdescribed herein, such an aggregated filter can advantageously reducethe number of filters and RF ports. FIG. 1 further shows that theswitching circuit 106 can include a switch path 108 that is configuredto accommodate the aggregated filtering functionality associated withthe aggregated filter 104. Various examples of such aggregated filtersand switched paths are described herein in greater detail.

Many designs for wireless devices such as smartphones and tablets desirelower cost and smaller size, while simultaneously increasing complexityand performance requirements. Radio-frequency (RF) front-end modules(FEMs) provide a platform where at least some of such designs can beimplemented. For example, functionalities associated with switching,filtering, and power amplifiers (PAs) can be implemented in a FEM, andsuch a design can be desirable due to an increase in the number ofnetworks, regions and technologies supported in modern devices.

As an example, it is noted that one of the challenges is to design aquadruplexer with acceptable insertion loss for system requirements,including new carrier aggregation technology that supports, for example,transmit in one TX band and receive in two RX bands simultaneously. As amore specific example, such carrier aggregation can include followingexample configurations. In an example configuration, Band 1 (B1) andBand 3 (B3) can be aggregated as follows: Transmit B1 and receive B1 andB3, or transmit B3 and receive B1 and B3. In another exampleconfiguration, Band 2 (B2) and Band 4 (B4) can be aggregated as follows:Transmit B2 and receive B2 and B4, or transmit B4 and receive B2 and B4.

In some situations, carrier aggregation can result in additional loss ina quadruplexer. Accordingly, a FEM may require PAs to deliver more RFpower, thereby increasing current consumption from the battery andincreasing thermal dissipation in related semiconductor devices.

Some conventional quadruplexer designs include a combination of twoduplexers (e.g., two TX and two RX filters) to a switch, and the switchcan be connected to an antenna. Such a design typically will increaseinsertion loss in the RF signal path significantly due to the loadingeffect of unused filters.

In the context of an FEM having most or all of the RF content between atransceiver and an antenna, such an FEM can include an antenna switchmodule (ASM), filters for transmit and receive bands, and poweramplifiers (PAs). With such a FEM covering a significant number of bandsin a single package, the result can be a vast network of filters,duplexers, and power amplifiers.

In current FEM designs, the ASM is typically used to switch and selectthe band in use and electrically connect it to the antenna. Forfrequency-division duplexing (FDD) 3G and 4G networks, the selected pathon the ASM is typically used for both transmit and receive functions. Aduplexer for each band can provide the filtering necessary or desiredfor transmit and receive paths. Thus, a duplexer is typically requiredfor each of the many bands implemented in such an FEM design.

Disclosed herein are examples of architectures, circuits and methodsrelated to a FEM having carrier aggregation which can be implementedwhile maintaining performance in one or more areas within acceptablerange(s). Such examples of carrier aggregation are described in thecontext of Bands 1, 2, 3 and 4 (B1, B2, B3 and B4); however, it will beunderstood that one or more features of the present disclosure can alsobe implemented in other combinations of bands. It will also beunderstood that one or more features of the present disclosure can alsobe implemented in architectures where various components are notnecessarily within a single module.

In some implementations, a switched multiplexer architecture can beconfigured to utilize one or more overlapping frequency ranges amongdifferent bands. For example, in the context of B1, B2, B3 and B4,frequency ranges associated with these example bands are listed in Table1.

TABLE 1 Band TX Frequency (MHz) RX Frequency (MHz) B1 1920 to 1980 2110to 2170 B2 1850 to 1910 1930 to 1990 B3 1710 to 1785 1805 to 1880 B41710 to 1755 2110 to 2155One can see that B4 receive frequency band lies within the B1 receivefrequency band, and B4 transmit frequency band lies within the B3transmit frequency band.

FIG. 2 show an example of a FEM architecture that utilizes aconventional implementation of B1, B3 and B4 bands. Although not shown,it will be understood that other bands can also be implemented in suchan architecture. One can see that each band includes a separateduplexer, and each duplexer includes TX and RX filters. Thus, there areat least six filters for the three example bands B1, B3 and B4. Thethree example duplexers corresponding to the foregoing three bands areshown to be in communication with an antenna port through an antennaswitching module (ASM).

Example: Switched Multiplexer Design for B1, B3 and B4:

FIG. 3 shows that in some embodiments, some or all of circuits andrelated components associated with the B4 duplexer can be removed,thereby reducing size and cost of the FEM considerably. In the contextof the example of FIG. 2, the entire duplexer for B4 can be removed,thereby reducing the number of filters by at least two.

In the example shown in FIG. 3, a first duplexer is shown to include aB1 TX filter and a B1/4 RX filter that can provide RX filteringfunctionality for B1 and B4. The B1 TX filter can be connected (e.g.,through a phase delay component) to a first switching node (e.g., afirst throw) of an antenna switch S1 of an ASM. The B1/4 RX filter canbe connected (e.g., through a phase delay component and a switch S2) tothe first switching node of the antenna switch S1.

In the example shown in FIG. 3, a second duplexer is shown to include aB3 RX filter and a B3/4 TX filter that can provide TX filteringfunctionality for B3 and B4. The B3 RX filter can be connected (e.g.,through a phase delay component) to a second switching node (e.g., asecond throw) of the antenna switch S1. The B3/4 TX filter can beconnected (e.g., through the same phase delay component for B3 RX) tothe second switching node of the antenna switch S1.

In the example shown in FIG. 3, the B1/4 RX filter can be connected(e.g., through a phase delay component and a switch S3) to the secondswitching node of the antenna switch S1. Accordingly, TX and RXoperations of B1, B3 and B4 can be effectuated by example switch stateslisted in Table 2.

TABLE 2 State TX RX S1 S2 S3 1 B1 B1 First throw 1 0 2 B3 B3 Secondthrow 0 0 3 B4 B1/B3/B4 Second throw 0 1 4 B1 B1/B3 First throw 1 1

In some embodiments, an ASM can include switches such as FET(field-effect transistor) SOI (silicon-on-insulator) switchesimplemented at selected paths to facilitate the example carrieraggregation configuration of FIG. 3. Although described in the contextof FET SOI switches, it will be understood that one or more features ofthe present disclosure can also be implemented utilizing other types ofswitches. In some embodiments, phase delay components such as phasedelay networks can be implemented as shown and described herein tofacilitate the corresponding example multiplexer topologies.

In some implementations, band filters (in a carrier-aggregatedconfiguration) that do not need to pass through an FET SOI can havesimilar or substantially identical filtering performance as theircounterparts in a non-carrier-aggregated configuration. In the exampleof FIG. 3, the performance of the transmit band filters (e.g., B1 TX,B3/4 TX) can be similar or substantially identical to the performanceassociated with the example of FIG. 2. B3 receive (B3 RX) can also havesimilar or substantially identical filtering performance as B3 RX of theexample of FIG. 2.

In the example shown in FIG. 3, in addition to the reduced number ofband filters, the number of receive and/or transmit ports (e.g., receiveoutputs) on the FEM can be reduced, allowing for a smaller FEM footprintand easier, potentially higher performance transceiver implementation.Additionally, the ASM in FIG. 3 has one fewer throw than the exampleconfiguration of FIG. 2, thereby allowing the ASM to be implemented in asmaller and a more cost-effective manner for the FEM.

In the example shown in FIG. 3, the receive bands for B1 and B4 canincur additional loss (e.g., 0.4 dB) in implementations where SOIswitches (S2 and/or S3) are utilized. Such an additional loss may beacceptable in some applications. In some embodiments, such SOI switchescan be configured to provide reduced loss, thereby reducing theforegoing example loss for B1/4 RX.

As described herein, the example configuration of FIG. 3 can have atleast two less band filters than the example of FIG. 2. Such reductionin the number of filters can provide an advantageous feature whereloading loss resulting from unused filters is reduced.

Example: Switched Multiplexer Design for B1 or B3 TX+B1 and B3 RX:

FIG. 4 shows that in some embodiments, a carrier aggregationconfiguration can be implemented to address 4G systems, including, forexample, LTEAdvanced, which is being standardized in 3GPP as part of LTERelease 10. The example configuration of FIG. 4 can allow, among others,scalable expansion of effective bandwidth delivered to a user terminalthrough concurrent utilization of radio resources across multiplecarriers. Such carriers utilize different bandwidths and may be in thesame or different bands to provide maximum or improved flexibility inutilizing a limited radio spectrum available to operators.

In the example shown in FIG. 4, a B1 TX filter can be connected to anantenna port of an ASM through a phase delay component and a switch S1.A B1/4 RX filter can be connected to the antenna port of the ASM througha phase delay component, a switch S3, and the switch S1. The B1/4 RXfilter can also be connected to the antenna port through a phase delaycomponent, a switch S4, and a switch S2. A B3 RX filter can be connectedto the antenna port of the ASM through a phase delay component, a switchS5, and the switch S1. The B3 RX filter can also be connected to theantenna port through a phase delay component, a switch S6, and theswitch S2. A B3/4 TX filter can be connected to the antenna port of theASM through a delay component and the switch S2. Accordingly, TX and RXoperations of B1, B3 and B4 can be effectuated by example switch stateslisted in Table 3.

TABLE 3 State TX RX S1 S2 S3 S4 S5 S6 1 B1 B1 1 0 1 0 0 0 2 B3 B3 0 1 00 0 1 3 B4 B4 0 1 0 1 0 0 4 B1 B1 & B3 1 0 1 0 1 0 5 B3 B1 & B3 0 1 0 10 1

In the example of FIG. 4, the performance of the transmit band filtersB1 TX and B3/4 TX can be similar or substantially identical to theperformance associated with a non-carrier-aggregated counterpart (e.g.,FIG. 2). The receive bands for B1, B3 and B4 can incur additional loss(e.g., 0.5 dB) in implementations where SOI switches (e.g., S3-S6) areutilized. However, such a loss can be relatively small when compared toloss (e.g., 1.0 dB) resulting from an extra duplexer associated with anon-carrier-aggregated configuration such as the example of FIG. 2. Insome embodiments, such SOI switches can be configured to provide reducedloss, thereby reducing the foregoing example loss for the receive bandsfor B1, B3 and B4.

In the example shown in FIG. 4, in addition to the reduced number ofband filters, the number of receive and/or transmit ports (e.g., receiveoutputs) on the FEM can be reduced, allowing for a smaller FEM footprintand easier, potentially higher performance transceiver implementation.Further, the example carrier-aggregation configuration of FIG. 4 canalso be modified to support a more complex multi-band carrieraggregation designs.

Example: Switched Multiplexer Design for B1/3TX+B1&3RX & B2/4TX+B2&4RX:

FIG. 5 shows that in some embodiments, a carrier aggregationconfiguration such as the example of FIG. 4 can be modified toaccommodate more complex designs. In the example shown in FIG. 5, B2band capability is added, and aggregation of at least some portion ofsuch an additional band can be implemented.

In the example shown in FIG. 5, B1 TX, B1/4 RX, B3 RX and B3/4 TXfilters can be connected to an antenna port of an ASM through phasedelay components and switches S1-S6 in similar manners as described inreference to FIG. 4. Additionally, the B1/4 RX filter can be connectedto the antenna port of the ASM through its corresponding phase delaycomponent, a switch S7, and a switch S10. A B2 TX filter can beconnected to the antenna port through a phase delay component and theswitch S10. A B2 RX filter can be connected to the antenna port througha phase delay component, a switch S8, and the switch S2. The B2 RXfilter can also be connected to the antenna port through a phase delaycomponent, a switch S9, and the switch S10. Accordingly, TX and RXoperations of B1, B2, B3 and B4 can be effectuated by example switchstates listed in Table 4.

TABLE 4 State TX RX S1 S2 S3 S4 S5 S6 S7 S8 S9 S10 1 B1 B1 1 0 1 0 0 0 00 0 0 2 B2 B2 0 0 0 0 0 0 0 0 1 1 3 B3 B3 0 1 0 0 0 1 0 0 0 0 4 B4 B4 01 0 1 0 0 0 0 0 0 5 B1 B1 & 3 1 0 1 0 1 0 0 0 0 0 6 B3 B1 & 3 0 1 0 1 01 0 0 0 0 7 B2 B2 & 4 0 0 0 0 0 0 1 0 1 1 8 B4 B2 & 4 0 1 0 1 0 0 0 1 00

In the example of FIG. 5, the performance of the transmit band filtersB1 TX, B3/4 TX and B2 TX can be similar or substantially identical tothe performance associated with a non-carrier-aggregated counterpart.The receive bands for B1, B2, B3 and B4 can incur additional loss inimplementations where SOI switches (e.g., S3-S9) are utilized. However,such a loss can be relatively small when compared to loss resulting froman extra duplexer(s) associated with a non-carrier-aggregatedconfiguration. In some embodiments, such SOI switches can be configuredto provide reduced loss, thereby reducing the foregoing example loss forthe receive bands for B1, B2, B3 and B4.

In the example shown in FIG. 5, in addition to the reduced number ofband filters, the number of receive and/or transmit ports (e.g., receiveoutputs) on the FEM can be reduced, allowing for a smaller FEM footprintand easier, potentially higher performance transceiver implementation.

Additional Examples of Switched Multiplexer Designs:

FIGS. 6-11 show additional examples related to switched multiplexerdesigns. In many smart mobile device designs, lower cost and smallersize are desirable features in front-end modules (FEMs), whilesimultaneously increasing complexity and requirements in device designs.Currently, many smart mobile devices support, for example, 2G:GSMQuadband, 3G/4G FDD:B1, 2, (3 or 4), 5, 7, 8, 13, (17 or 20) without LTEcarrier aggregation; and TDD:B38, B39, B40 without LTE carrieraggregation. Next generation and/or other future designs in many smartmobile devices can support, for example, 2G:GSM quadband, 3G/4G FDD:B1,2, 3, 4, 5, 7, 8, 12, 13, (17 or 20) with LTE carrier aggregation. Suchcarrier aggregation can include, for example, (1) two carrieraggregation with one HB Rx(B1, 2, 3, 4, 7) and one LB Rx (B5, 8, 17,20); (2) three carrier aggregation with two HB Rx(B1+7, B2+4, B3+7) andone LB Rx; and/or (3) three carrier aggregation with two LB Rx(B5+12,B5+17, B8+20) and one HB Rx. The foregoing next generation and/or otherfuture designs can also support, for example, TDD:B30, B38, B39, B40,B41, with LTE carrier aggregation for B40(B40A, B40B), B41(B41A, B41B,B41C).

FIG. 6 shows an example of a front-end module (FEM) 10 that utilizes atraditional duplexer and quadruplexer design to support LTE carrieraggregation. The example FEM 10 is shown to include an antenna switchsystem having a high-band antenna switch module (ASM) (HB_ASM) 12 and alow-band ASM (LB_ASM) 14. The high-band ASM (HB_ASM) 12 is shown toprovide switching functionality between a high-band antenna (HB_ANT) anda number of frequency bands. The low-band ASM (LB_ASM) 14 is shown toprovide switching functionality between a low-band antenna (LB_ANT) anda number of frequency bands. In FIG. 6, each of circuits depicted asblocks M1, M2, M3, M4A, M4B, M5, M6A, M6B, M7, M8, M9, M10, M11, M12,N1A, N1B, N2, N3A, N3B, N4, N5 and N6 can be configured to provideimpedance matching and/or phase shifting functionality (e.g., utilizingL and/or C elements).

In the example of FIG. 6, switch S1 is shown to provide a switchablepath between HB_ANT and FDD_HB_TRX1 (frequency-division duplex,high-band, transceiver channel 1) through M1. Similarly, switch S2 isshown to provide a switchable path between HB_ANT and FDD_HB_TRX2(frequency-division duplex, high-band, transceiver channel 2) throughM2. Similarly, switch S3 is shown to provide a switchable path betweenHB_ANT and FDD_HB_TRX3 (frequency-division duplex, high-band,transceiver channel 3) through M3.

In the example of FIG. 6, switch S4 is shown to provide a switchablepath between HB_ANT and a quadruplexer 20 that includes a B1 duplexerand a B7 duplexer. The B1 duplexer is shown to be coupled to S4 throughM4A, and the B7 duplexer is shown to be coupled to S4 through M4B. TheB1 duplexer is shown to provide B1Tx/B1Rx duplex functionality, and theB7 duplexer is shown to provide B7Tx/B7Rx duplex functionality.

In the example of FIG. 6, switch S5 is shown to provide a switchablepath between HB_ANT and a B3 duplexer. The B3 duplexer is shown to becoupled to S5 through M5. The B3 duplexer is shown to provide B3Tx/B3Rxduplex functionality.

In the example of FIG. 6, switch S6 is shown to provide a switchablepath between HB_ANT and a quadruplexer 22 that includes a B2 duplexerand a B4 duplexer. The B2 duplexer is shown to be coupled to S6 throughM6A, and the B4 duplexer is shown to be coupled to S6 through M6B. TheB2 duplexer is shown to provide B2Tx/B2Rx duplex functionality, and theB4 duplexer is shown to provide B4Tx/B4Rx duplex functionality.

In the example of FIG. 6, switch S7 is shown to provide a switchablepath between HB_ANT and a filter for B30 or B34. The B30/B34 filter isshown to be coupled to S7 through M7. The B30/B34 filter is shown toprovide filtering functionality for Tx and Rx signals for B30 or B34.

In the example of FIG. 6, switch S8 is shown to provide a switchablepath between HB_ANT and a filter for B39. The B39 filter is shown to becoupled to S8 through M8. The B39 filter is shown to provide filteringfunctionality for Tx and Rx signals for B39.

In the example of FIG. 6, switch S9 is shown to provide a switchablepath between HB_ANT and a filter for B38 and B41B. The B38/B41B filteris shown to be coupled to S9 through M9. The B38/B41B filter is shown toprovide filtering functionality for Tx and Rx signals for B38 and/orB41B.

In the example of FIG. 6, switch S10 is shown to provide a switchablepath between HB_ANT and a duplexer for B40A and B41A. The B40A+B41Aduplexer is shown to be coupled to S10 through M10. The B40A+B41Aduplexer is shown to provide B40A_TRX/B41A_TRX duplex functionality.

In the example of FIG. 6, switch S11 is shown to provide a switchablepath between HB_ANT and a duplexer for B40B and B41C. The B40B+B41Cduplexer is shown to be coupled to S11 through M11. The B40B+B41Cduplexer is shown to provide B40B_TRX/B41C_TRX duplex functionality.

In the example of FIG. 6, switch S12 is shown to provide a switchablepath between HB_ANT and TDD_2GHB_Tx through M12. TDD_2GHB_Tx supports a2G time-division duplex high-band signal for transmission.

In the example of FIG. 6, switch T1 is shown to provide a switchablepath between LB_ANT and a quadruplexer 24 that includes a B5 duplexerand a B12 duplexer. The B5 duplexer is shown to be coupled to T1 throughN1A, and the B12 duplexer is shown to be coupled to T1 through N1B. TheB5 duplexer is shown to provide B5Tx/B5Rx duplex functionality, and theB12 duplexer is shown to provide B12Tx/B12Rx duplex functionality.

In the example of FIG. 6, switch T2 is shown to provide a switchablepath between LB_ANT and a B13 duplexer. The B13 duplexer is shown to becoupled to T2 through N2. The B13 duplexer is shown to provideB13Tx/B13Rx duplex functionality.

In the example of FIG. 6, switch T3 is shown to provide a switchablepath between LB_ANT and a quadruplexer 26 that includes a B8 duplexerand a B20 duplexer. The B8 duplexer is shown to be coupled to T3 throughN3A, and the B20 duplexer is shown to be coupled to T3 through N3B. TheB8 duplexer is shown to provide B8Tx/B8Rx duplex functionality, and theB20 duplexer is shown to provide B20Tx/B20Rx duplex functionality.

In the example of FIG. 6, switch T4 is shown to provide a switchablepath between LB_ANT and FDD_LBTRX1 (frequency-division duplex, low-band,transceiver channel 1) through N4. Similarly, switch T5 is shown toprovide a switchable path between LB_ANT and FDD_LB_TRX2(frequency-division duplex, low-band, transceiver channel 2) through N5.

In the example of FIG. 6, switch T6 is shown to provide a switchablepath between LB_ANT and TDD_2GLB_Tx through N6. TDD_2GLB_Tx supports a2G time-division duplex low-band signal for transmission.

As described in reference to FIG. 6, the two duplexers for B1 and B7 areelectrically connected together to form the quadruplexer 20. Similarly,the quadruplexer 22 is formed by the two duplexers for B2 and B4; thequadruplexer 24 is formed by the two duplexers for B5 and B12; and thequadruplexer 26 is formed by the two duplexers for B8 and B20. Whilesuch a quadruplexer design is relatively easier to implement, there maybe disadvantages. For example, insertion loss between the respectiveantenna (HB_ANT or LB_ANT) and the respective circuit (Tx or Rx) will behigher through such a quadruplexer (20, 22, 24 or 26) than insertionloss through an individual duplexer. Accordingly, such a configurationis not ideal for single band operation due to higher insertion losswhich typically translates to lower battery life and reduced RF signalreception performance in mobile devices. It is also noted that theexample configuration of FIG. 6 typically does not fully support LTEcarrier aggregation for the combinations B1+B7, B2+B4, B7+B3, B5+B12,B5+B17 and/or B8+B20.

FIG. 7 shows an example of a front-end module (FEM) 130 that utilizes adesign to, among others, support LTE carrier aggregation. The exampleFEM 130 is shown to include an antenna switch system having a high-bandantenna switch module (ASM) (HB_ASM) 132 and a low-band ASM (LB_ASM)134. The high-band ASM (HB_ASM) 132 is shown to provide switchingfunctionality between a high-band antenna (HB_ANT) and a number offrequency band channels. The low-band ASM (LB_ASM) 134 is shown toprovide switching functionality between a low-band antenna (LB_ANT) anda number of frequency band channels. In FIG. 7, each of circuitsdepicted as blocks M1, M2, M3, M4, M5, M6, M7, M8, M9, M10, M11, M12,N1, N2, N3, N4, N5, N6 and N7 can be configured to provide impedancematching and/or phase shifting functionality (e.g., utilizing L and/or Celements).

In the example of FIG. 7, switch S1 is shown to provide a switchablepath between HB_ANT and FDD_HB_TRX1 (frequency-division duplex,high-band, transceiver channel 1) through M1. Although not shown, one ormore other FDD_HB_TRX channels can be supported in a similar manner.

In the example of FIG. 7, switch S2 is shown to provide a switchablepath between HB_ANT and a B1 duplexer. The B1 duplexer is shown to becoupled to S2 through M2. The B1 duplexer is shown to provide B1Tx/B1Rxduplex functionality. Similarly, switch S3 is shown to provide aswitchable path between HB_ANT and a B7 duplexer. The B7 duplexer isshown to be coupled to S3 through M3. The B7 duplexer is shown toprovide B7Tx/B7Rx duplex functionality.

In the foregoing example of B1 and B7 duplexers and their respectiveswitches S2 and S3, such a combination (indicated as 140) can provide,among others, multiplexing functionality of the example quadruplexer 20of FIG. 6. Further, because each of the B1 and B7 duplexers hasassociated with it a separate switch (S2, S3), operation of one duplexer(B1 or B7) can be achieved independently from the other duplexer (B7 orB1). Other advantageous features associated with the combination 140 aredescribed herein in greater detail.

In the example of FIG. 7, switch S4 is shown to provide a switchablepath between HB_ANT and a B3 duplexer. The B3 duplexer is shown to becoupled to S4 through M4. The B3 duplexer is shown to provide B3Tx/B3Rxduplex functionality.

In the example of FIG. 7, switch S5 is shown to provide a switchablepath between HB_ANT and a B2 duplexer. The B2 duplexer is shown to becoupled to S5 through M5. The B2 duplexer is shown to provide B2Tx/B2Rxduplex functionality. Similarly, switch S6 is shown to provide aswitchable path between HB_ANT and a B4 duplexer. The B4 duplexer isshown to be coupled to S6 through M6. The B4 duplexer is shown toprovide B4Tx/B4Rx duplex functionality.

In the foregoing example of B2 and B4 duplexers and their respectiveswitches S5 and S6, such a combination (indicated as 142) can provide,among others, multiplexing functionality of the example quadruplexer 22of FIG. 6. Further, because each of the B2 and B4 duplexers hasassociated with it a separate switch (S5, S6), operation of one duplexer(B2 or B4) can be achieved independently from the other duplexer (B4 orB2). Other advantageous features associated with the combination 142 aredescribed herein in greater detail.

In the example of FIG. 7, switch S7 is shown to provide a switchablepath between HB_ANT and a filter for B30 or B34. The B30/B34 filter isshown to be coupled to S7 through M7. The B30/B34 filter is shown toprovide filtering functionality for Tx and Rx signals for B30 or B34.

In the example of FIG. 7, switch S8 is shown to provide a switchablepath between HB_ANT and a filter for B39. The B39 filter is shown to becoupled to S8 through M8. The B39 filter is shown to provide filteringfunctionality for Tx and Rx signals for B39.

In the example of FIG. 7, switch S9 is shown to provide a switchablepath between HB_ANT and a filter for B38 and B41B. The B38/B41B filteris shown to be coupled to S9 through M9. The B38/B41B filter is shown toprovide filtering functionality for Tx and Rx signals for B38 and/orB41B.

In the example of FIG. 7, switch S10 is shown to provide a switchablepath between HB_ANT and a duplexer for B40A and B41A. The B40A+B41Aduplexer is shown to be coupled to S10 through M10. The B40A+B41Aduplexer is shown to provide B40A_TRX/B41A_TRX duplex functionality.

In the example of FIG. 7, switch S11 is shown to provide a switchablepath between HB_ANT and a duplexer for B40B and B41C. The B40B+B41Cduplexer is shown to be coupled to S11 through M11. The B40B+B41Cduplexer is shown to provide B40B_TRX/B41C_TRX duplex functionality.

In the example of FIG. 7, switch S12 is shown to provide a switchablepath between HB_ANT and TDD_2GHB_Tx through M12. TDD_2GHB_Tx supports a2G time-division duplex high-band signal for transmission.

In the example of FIG. 7, switch T1 is shown to provide a switchablepath between LB_ANT and a B5 duplexer. The B5 duplexer is shown to becoupled to T1 through N1. The B5 duplexer is shown to provide B5Tx/B5Rxduplex functionality. Similarly, switch T2 is shown to provide aswitchable path between LB_ANT and a B12 duplexer. The B12 duplexer isshown to be coupled to T2 through N2. The B12 duplexer is shown toprovide B12Tx/B12Rx duplex functionality.

In the foregoing example of B5 and B12 duplexers and their respectiveswitches T1 and T2, such a combination (indicated as 144) can provide,among others, multiplexing functionality of the example quadruplexer 24of FIG. 6. Further, because each of the B5 and B12 duplexers hasassociated with it a separate switch (T1, T2), operation of one duplexer(B5 or B12) can be achieved independently from the other duplexer (B12or B5). Other advantageous features associated with the combination 144are described herein in greater detail.

In the example of FIG. 7, switch T3 is shown to provide a switchablepath between LB_ANT and a B8 duplexer. The B8 duplexer is shown to becoupled to T3 through N3. The B8 duplexer is shown to provide B8Tx/B8Rxduplex functionality. Similarly, switch T5 is shown to provide aswitchable path between LB_ANT and a duplexer for B17 or B20. TheB17/B20 duplexer is shown to be coupled to T5 through N5. The B12duplexer is shown to provide B17Tx/B17Rx or B20Tx/B20Rx duplexfunctionality.

In the foregoing example of B8 and B17/B20 duplexers and theirrespective switches T3 and T5, such a combination (indicated as 146) canprovide, among others, multiplexing functionality of the examplequadruplexer 26 of FIG. 6. Further, because each of the B8 and B17/B20duplexers has associated with it a separate switch (T3, T5), operationof one duplexer (B8 or B17/B20) can be achieved independently from theother duplexer (B17/B20 or B8). It is further noted that because of theB17/B20 duplexer's capability of providing duplexing for B17 or B20,additional multiplexing flexibility can be realized. Other advantageousfeatures associated with the combination 146 are described herein ingreater detail.

In the example of FIG. 7, switch T4 is shown to provide a switchablepath between LB_ANT and a B13 duplexer. The B13 duplexer is shown to becoupled to T4 through N4. The B13 duplexer is shown to provideB13Tx/B13Rx duplex functionality.

In the example of FIG. 7, switch T6 is shown to provide a switchablepath between LB_ANT and TDD_2GLB_Tx through N6. TDD_2GLB_Tx supports a2G time-division duplex low-band signal for transmission.

In the example of FIG. 7, switch T7 is shown to provide a switchablepath between LB_ANT and LB_TRX1 (low-band, transceiver channel 1)through N7. Although not shown, one or more other LB_TRX channels can besupported in a similar manner.

As described in reference to FIG. 7, quadruplexing functionality can beachieved by configuring selected switches in the ASM (132 and/or 134)associated with two duplexers. For example, quadruplexing functionality(depicted as 140) for B1 and B7 can be achieved by turning ON each ofthe switches S2 and S3. In another example, quadruplexing functionality(depicted as 142) for B2 and B4 can be achieved by turning ON each ofthe switches S5 and S6. In yet another example, quadruplexingfunctionality (depicted as 144) for B5 and B12 can be achieved byturning ON each of the switches T1 and T2. In yet another example,quadruplexing functionality (depicted as 146) for B8 and B20 can beachieved by turning ON each of the switches T3 and T5.

The foregoing examples of quadruplexing configurations 140, 142, 144,146 are those that correspond to the example quadruplexers 20, 22, 24,26 of FIG. 6. Other quadruplexing configurations can be formed in theexample of FIG. 7. For example, quadruplexing functionality for B3 andB7 can be achieved by turning ON each of the switches S4 and S3. Inanother example, quadruplexing functionality for B5 and B17 can beachieved by turning ON each of the switches T1 and T5.

In the context of the foregoing B3+B7 quadruplexing functionality, it isnoted that for the configuration of FIG. 6 to achieve such afunctionality, the switches S4 and S5 (in FIG. 6) can be turned ON.However, because S4 (of FIG. 6) is already tied to the quadruplexer 20,the B3+B7 quadruplexing functionality is either not possible (e.g., dueto the presence of B1 in the quadruplexer 20), or suffers from anincreased insertion loss associated with the quadruplexer 20. Similarly,in the context of the foregoing B5+B17 quadruplexing functionality, itis noted that in the configuration of FIG. 6, B5 is tied to B12 in thequadruplexer 24. Accordingly, the B5+B17 quadruplexing functionality iseither not possible (e.g., due to the presence of B12 in thequadruplexer 24), or suffers from an increased insertion loss associatedwith the quadruplexer 24.

The example switched multiplexer design of FIG. 7 can provide a numberof significant benefits. For example, an insertion loss between therespective antenna (HB_ANT or LB_ANT) and the respective circuit (Tx orRx) in a quadruplexing configuration can be similar to an insertion lossassociated with an individual duplexer. Further, the exampleconfiguration of FIG. 7 can fully support LTE carrier aggregation forthe combinations B1+B7, B2+B4, B7+B3, B5+B12, B5+B17 and/or B8+B20.Accordingly, such benefits can include, for example, eliminating orreducing the need for designing and implementing multiple parts tosupport wireless operations in different regions.

FIG. 8 shows another example of a front-end module (FEM) 150 thatutilizes a design to, among others, support LTE carrier aggregation. Theexample FEM 150 is shown to include an antenna switch system having ahigh-band antenna switch module (ASM) (HB_ASM) 152 and a low-band ASM(LB_ASM) 154. The high-band ASM (HB_ASM) 152 is shown to provideswitching functionality between a high-band antenna (HB_ANT) and anumber of frequency band channels. The low-band ASM (LB_ASM) 154 isshown to provide switching functionality between a low-band antenna(LB_ANT) and a number of frequency band channels. In FIG. 8, each ofcircuits depicted as blocks M1, M2, M3, M4, M5, M6, M7, M8, M9, M10,M11, M12, N1, N2, N3, N4, N5, N6 and N7 can be configured to provideimpedance matching and/or phase shifting functionality (e.g., utilizingL and/or C elements).

In the example of FIG. 8, switch S1 is shown to provide a switchablepath between HB_ANT and a B1(Tx) filter through M1. Switch S2 is shownto provide a switchable path between HB_ANT and an Rx filter for B1 andB4 through M2. Switch S3 is shown to provide a switchable path betweenHB_ANT and a B7 duplexer through M3. The B7 duplexer is shown to provideB7Tx/B7Rx duplex functionality.

In the foregoing example, a combination of the B1 filters (B1(Tx) andB1/4(Rx)), the B7 duplexer and their respective switches S1, S2 and S3,can provide, among others, multiplexing functionality (depicted as 160)of the example quadruplexer 20 of FIG. 6. Further, because each of theB1 filters and the B7 duplexer has associated with it a separate switch(S1, S2, S3), operation of one path can be achieved independently fromthe other paths. Other advantageous features associated with thecombination 160 are described herein in greater detail.

In the example of FIG. 8, switch S4 is shown to provide a switchablepath between HB_ANT and a Tx filter for B3 and B4 through M4. Switch S5is shown to provide a switchable path between HB_ANT and a B3(Rx) filterthrough M5. Switch S6 is shown to provide a switchable path betweenHB_ANT and a B2 duplexer through M6. The B2 duplexer is shown to provideB2Tx/B2Rx duplex functionality.

As shown in FIG. 8, a combination of the Tx and Rx filters for B4 (e.g.,B3/4(Tx) and B1/4(Rx)), the B2 duplexer and their respective switchesS4, S2 and S6, can provide, among others, multiplexing functionality(depicted as 162) of the example quadruplexer 22 of FIG. 6. Further,because each of the B4 filters and the B2 duplexer has associated withit a separate switch (S4, S2, S6), operation of one path can be achievedindependently from the other paths. Other advantageous featuresassociated with the combination 162 are described herein in greaterdetail.

In the example of FIG. 8, switch S7 is shown to provide a switchablepath between HB_ANT and a filter for B30 or B34. The B30/B34 filter isshown to be coupled to S7 through M7. The B30/B34 filter is shown toprovide filtering functionality for Tx and Rx signals for B30 or B34.

In the example of FIG. 8, switch S8 is shown to provide a switchablepath between HB_ANT and a filter for B39. The B39 filter is shown to becoupled to S8 through M8. The B39 filter is shown to provide filteringfunctionality for Tx and Rx signals for B39.

In the example of FIG. 8, switch S9 is shown to provide a switchablepath between HB_ANT and a filter for B38 and B41B. The B38/B41B filteris shown to be coupled to S9 through M9. The B38/B41B filter is shown toprovide filtering functionality for Tx and Rx signals for B38 and/orB41B.

In the example of FIG. 8, switch S10 is shown to provide a switchablepath between HB_ANT and a duplexer for B40A and B41A. The B40A+B41Aduplexer is shown to be coupled to S10 through M10. The B40A+B41Aduplexer is shown to provide B40A_TRX/B41A_TRX duplex functionality.

In the example of FIG. 8, switch S11 is shown to provide a switchablepath between HB_ANT and a duplexer for B40B and B41C. The B40B+B41Cduplexer is shown to be coupled to S11 through M11. The B40B+B41Cduplexer is shown to provide B40B_TRX/B41C_TRX duplex functionality.

In the example of FIG. 8, switch S12 is shown to provide a switchablepath between HB_ANT and TDD_2GHB_Tx through M12. TDD_2GHB_Tx supports a2G time-division duplex high-band signal for transmission.

In the example of FIG. 8, switch T1 is shown to provide a switchablepath between LB_ANT and a B5 duplexer. The B5 duplexer is shown to becoupled to T1 through N1. The B5 duplexer is shown to provide B5Tx/B5Rxduplex functionality. Similarly, switch T2 is shown to provide aswitchable path between LB_ANT and a B12 duplexer. The B12 duplexer isshown to be coupled to T2 through N2. The B12 duplexer is shown toprovide B12Tx/B12Rx duplex functionality.

In the foregoing example of B5 and B12 duplexers and their respectiveswitches T1 and T2, such a combination (indicated as 164) can provide,among others, multiplexing functionality of the example quadruplexer 24of FIG. 6. Further, because each of the B5 and B12 duplexers hasassociated with it a separate switch (T1, T2), operation of one duplexer(B5 or B12) can be achieved independently from the other duplexer (B12or B5). Other advantageous features associated with the combination 164are described herein in greater detail.

In the example of FIG. 8, switch T3 is shown to provide a switchablepath between LB_ANT and a B8 duplexer. The B8 duplexer is shown to becoupled to T3 through N3. The B8 duplexer is shown to provide B8Tx/B8Rxduplex functionality. Similarly, switch T5 is shown to provide aswitchable path between LB_ANT and a duplexer for B17 or B20. TheB17/B20 duplexer is shown to be coupled to T5 through N5. The B12duplexer is shown to provide B17Tx/B17Rx or B20Tx/B20Rx duplexfunctionality.

In the foregoing example of B8 and B17/B20 duplexers and theirrespective switches T3 and T5, such a combination (indicated as 166) canprovide, among others, multiplexing functionality of the examplequadruplexer 26 of FIG. 6. Further, because each of the B8 and B17/B20duplexers has associated with it a separate switch (T3, T5), operationof one duplexer (B8 or B17/B20) can be achieved independently from theother duplexer (B17/B20 or B8). It is further noted that because of theB17/B20 duplexer's capability of providing duplexing for B17 or B20,additional multiplexing flexibility can be realized. Other advantageousfeatures associated with the combination 166 are described herein ingreater detail.

In the example of FIG. 8, switch T4 is shown to provide a switchablepath between LB_ANT and a B13 duplexer. The B13 duplexer is shown to becoupled to T4 through N4. The B13 duplexer is shown to provideB13Tx/B13Rx duplex functionality.

In the example of FIG. 8, switch T6 is shown to provide a switchablepath between LB_ANT and TDD_2GLB_Tx through N6. TDD_2GLB_Tx supports a2G time-division duplex low-band signal for transmission.

In the example of FIG. 8, switch T7 is shown to provide a switchablepath between LB_ANT and LB_TRX1 (low-band, transceiver channel 1)through N7. Although not shown, one or more other LB_TRX channels can besupported in a similar manner.

As described in reference to FIG. 8, quadruplexing functionality can beachieved by configuring selected switches in the ASM (132 and/or 134)associated with a combination of filters and/or duplexers. For example,quadruplexing functionality (depicted as 160) for B1 and B7 can beachieved by turning ON each of the switches S1, S2 and S3. In anotherexample, quadruplexing functionality (depicted as 162) for B2 and B4 canbe achieved by turning ON each of the switches S6, S4 and S2. In yetanother example, quadruplexing functionality (depicted as 164) for B5and B12 can be achieved by turning ON each of the switches T1 and T2. Inyet another example, quadruplexing functionality (depicted as 166) forB8 and B20 can be achieved by turning ON each of the switches T3 and T5.

The foregoing examples of quadruplexing configurations 160, 162, 164,166 are those that correspond to the example quadruplexers 20, 22, 24,26 of FIG. 6. Other quadruplexing configurations can be formed in theexample of FIG. 8. For example, quadruplexing functionality for B3 andB7 can be achieved by turning ON each of the switches S4, S5 and S3. Inanother example, quadruplexing functionality for B5 and B17 can beachieved by turning ON each of the switches T1 and T5.

FIG. 8 shows that duplexing functionality can be achieved by configuringselected switches in the ASM (132 and/or 134) associated with acombination of individual filters. For example, duplexing functionalityfor B1 can be achieved by turning ON each of the switches S1 and S2. Inanother example, duplexing functionality for B3 can be achieved byturning ON each of the switches S4 and S5. In yet another example,duplexing functionality for B4 can be achieved by turning ON each of theswitches S4 and S2.

The example switched multiplexer design of FIG. 8 can provide a numberof significant benefits. For example, an insertion loss between therespective antenna (HB_ANT or LB_ANT) and the respective circuit (Tx orRx) in a quadruplexing configuration can be similar to an insertion lossassociated with an individual duplexer when two duplexers are utilized.

When duplexing and/or multiplexing functionality is achieved byindividual filters, advantageous features such as increased flexibilityand/or additional improvement in insertion loss performance can beobtained. For example, in FIG. 8, B4 duplexer has been removed, andsimilar functionality can be provided by individual filters (e.g.,B3/4(Tx) and B1/4(Rx) filters). For such filters where each of the B3/B4Tx pair and the B1/B4 Rx pair can be co-banded (e.g., with no B4 Rxrouting), reduction in cost and/or size of FEMs can be realized. Inanother example, by physically separating the Tx and Rx filters for B1and B3, common ground inductor and coupling between Tx and Rx filterscan be eliminated. Accordingly, Tx-Rx isolation of B1, B3 and B4 canyield an improvement in performance over the example of FIG. 6.

It is also noted that the example configuration of FIG. 8 can fullysupport LTE carrier aggregation for the combinations B1+B7, B2+B4,B7+B3, B5+B12, B5+B17 and/or B8+B20. Accordingly, benefits associatedwith the example of FIG. 8 can include, for example, eliminating orreducing the need for designing and implementing multiple parts tosupport wireless operations in different regions.

In the examples of FIGS. 7 and 8, various switches in the ASMs can becontrolled through, for example, Mobile Industry Processor Interface(MIPI). For example, switches S1-S12 and T1-T7 of FIG. 7 and switchesS1-S12 and T1-T7 of Figure can be controlled by MIPI. Other controltechniques can also be utilized.

In some embodiments, a switched multiplexer can be configured to improveperformance of a difficult band. For example, filters for B25 aretypically heavily constrained due to a very narrow duplex gap, anddesigns typically do not have the degrees of freedom needed or desiredto absorb additional matching requirements of a quadruplexer.

FIG. 9 shows an example of a switched multiplexing configuration 170that can be implemented to support LTE carrier aggregation for B25+B4,B1+B7 and B3+B7. In the example of FIG. 9, filtering for B25Rx is shownto be split into B25A_Rx and B25B_Rx filters to reduce Ant_Rx insertionloss (e.g. between the antenna HB_ANT and B25Rx circuits). To formquadruplexing functionality for the B25+B4 combination, switches S7, S8on an ASM (HB_ASM) 172 and associated with the B25A_Rx and B25B_Rxfilters, switch S6 on the ASM 172 and associated with a B25_Tx filter,and switches S4, S2 on the ASM 172 and associated with B3/4_Tx andB1/4_Rx filters can be operated to yield desirable quadruplexingfunctionalities. For example, S6, S7, S4 and S2 can be turned ON to forma B25A+B4 quadruplexer. In another example, S6, S8, S4 and S2 can beturned ON to form a B25B+B4 quadruplexer.

In some embodiments, filters such as B25A_Rx and B25B_Rx can beimplemented with silicon-on-insulator (SOI) technology instead of morecostly thin-film bulk acoustic resonator (FBAR) technology.

In some embodiments, a switched multiplexer can be configured to provideimproved performance of harmonics radiation at an antenna. For example,a second harmonic (2f₀) of B8 Tx can fall in B3 Rx, such that B8 Txharmonics generated by a PA can leak into LB_ANT and couple into HB_ANT.Accordingly, more robust 2f₀ rejection at LB_ANT for B8 can bedesirable.

An option to address such a harmonic problem is to add a low-pass filter(LPF) at LB_ANT. However, such an addition can incur additional loss forall other LBs.

FIG. 10 shows an example of a switched multiplexing configuration 180that can address the foregoing harmonic problem. In such aconfiguration, rejection of the second harmonic (2f₀) of B8 can beachieved through switches on an ASM 182 without incurring significantadditional loss for all other LBs. For example, filter FL1 can beimplemented between a B8 duplexer and a switch T3 of the ASM 182. Theswitch T3 is shown to provide a switchable path between the B8 duplexerand the antenna LB_ANT.

The filter FL1 can be configured as, for example, a 2f₀ notch filter.When the switch T3 is turned ON, such a filter (FL1) can providerejection of 2f₀ at the antenna LB_ANT. In some embodiments, a secondfilter FL2 (e.g., a 2f₀ notch filter) can provide a shunt path to groundfrom the antenna LB_ANT and through a switch T7 on the ASM 182. Thus,when the switch T3 is turned ON, the switch T7 can also be turned on toprovide additional rejection of 2f₀ at the antenna LB_ANT.

Accordingly, one can see that by utilizing filter switching as shown byway of examples in FIG. 10, removal (e.g., by notching out) of unwantedsignals. As also described herein, such removal of unwanted signals canbe achieved while incurring little or minimum loss.

In the various examples described in reference to FIGS. 3-10, a circuitblock between a quadruplexer, a duplexer, or a filter and acorresponding switch in an ASM is described as, for example, animpedance matching circuit, a phase shifting (e.g., phase delay)circuit, or a filter (e.g., a notch filter) circuit. FIG. 11 shows thatin some embodiments, such a phase shifting circuit can be configured toprovide adjustable or tunable phase.

In FIG. 11, an example switched-in filter configuration 250 is shown toinclude a first duplexer 214 coupled to its corresponding switch on anASM 252 through a fixed phase shifting circuit 260 and a tunable phaseshifting circuit 262. As described herein, such a switch on the ASM canprovide a switchable path between the first duplexer 214 and an antennaport 256. Similarly, a second duplexer 224 is shown to be coupled to itscorresponding switch on the ASM 252 through a fixed phase shiftingcircuit 270 and a tunable phase shifting circuit 272.

As described herein, such a switch on the ASM can provide a switchablepath between the second duplexer 224 and the antenna port 256. Asdescribed herein, operation of the switches for the first and secondduplexers 214, 224 can allow the two duplexers to operate as aquadruplexer (e.g., when both switches are turned ON).

In the example of FIG. 11, the first duplexer 214 is shown to facilitatetransmission of an RF signal from a power amplifier 210 through amatching network 212. The first duplexer 214 is also shown to facilitatepassage of a first Rx signal. Similarly, the second duplexer 224 isshown to facilitate transmission of an RF signal from a power amplifier220 through a matching network 222; and also facilitate passage of asecond Rx signal. Although described in the context of duplexers, itwill be understood that such switched-in components can also include afilter without duplexing capability.

In some embodiments, each of the fixed phase shifting circuits 260, 270can also be configured to provide harmonic shunt capability forfiltering functionality. An example of such a configuration is describedherein in reference to FIG. 10.

In some embodiments, each of the tunable phase shifting circuits 262,272 can be configured to be electrically tunable to yield a desirablephase and/or impedance. Such electrical tunability can be facilitatedby, for example, a tunable-phase array that includes digitally switchedcapacitances (e.g., capacitors) arranged in series and/or in shuntconfigurations. In some embodiments, such an array of capacitors can beimplemented on the ASM. In some embodiments, shunt capacitance can beimplemented as a tunable phase shifting circuit, due to its relativelylow insertion loss impact.

The foregoing example of phase tuning can facilitate important phaserelationship between switched-in filters and/or duplexers as describedherein. For example, series or shunt arrangements of capacitance canchange the impedance and/or phase relationship between two (or more)filters and/or duplexers.

As described herein, a duplexer can be separated into Tx and Rx filters,and each of such filters can be coupled with an antenna through aseparate switch in an ASM. As also described herein, a quadruplexer canbe separated into duplexers, filters, or some combination thereof, andeach of such separated components can be coupled with an antenna througha separate switch in an ASM.

As also described herein, the separate switches associated with theseparated components (e.g., duplexers and/or filters) provides increasedflexibility in how multiplexer (e.g., quadruplexer) and/or duplexerfunctionalities can be obtained. In some embodiments, suchfunctionalities can be obtained with reduced insertion loss associatedwith the separated components.

Examples of Variations, Applications and Advantages:

In some implementations, one or more features of the present disclosurecan be based on a concept of splitting a duplexer into separate TX andRX filters, which can then be electrically connected to one or moreantenna ports through a switching network of an ASM. Suchimplementations can provide a number of advantageous features, and/or beapplied in different applications.

For example, one or more features of the present disclosure can allowimplementation of film bulk acoustic resonator (FBAR) duplexerfunctionality with desirable performance. Additionally, a number ofadvantageous features can be realized, including, for example, lessexpensive, more accessible, and/or potentially smaller surface acousticwave (SAW) filter technology.

In another example, one or more features of the present disclosure canenable high isolation zero cross-over layouts for highly integratedFEMs. Such desirable performance can be realized by, for example,avoiding or reducing TX-RX, Ant-TX, and/or Ant-RX cross-overs oftenrequired or present in duplexer layouts.

In yet another example, one or more features of the present disclosurecan allow enhanced isolation through increased physical separation of TXand RX components. For example, various examples described herein caninclude a reduced number of band filters, as well as a reduced number ofreceive and/or transmit ports. Accordingly, such reductions in TX and RXcomponents can allow reduction in FEM footprint, increase in physicalseparation of the TX and RX components, or some combination thereof.

In yet another example, one or more features of the present disclosurecan allow co-banding of different bands through frequency-divisionduplexing (FDD) filters. For example, 2G and time-division duplexing(TDD) systems can be co-banded through FDD RX filters, even inmulti-band context. Such co-banding can be achieved with little or nopenalty for duplexer filtering since it is switched out electricallythereby leaving only RX filter(s).

In yet another example, one or more features of the present disclosurecan allow architectures that are capable of flexibly connecting tofront-ends that utilize separate TX and RX antennas and/or antennafeeds. Such separate TX and RX antennas and/or antenna feeds can furtherenhance the isolation benefits provided by the antenna-to-antennaisolation.

In yet another example, one or more features of the present disclosurecan allow implementation of electrically tunable ganging of filters toenable carrier-aggregation of difficult band combinations. For example,combinations such as B2/B4, B3/B7, B17/B5, etc. can be aggregated withlittle or no performance degradation when compared to their respectivenon-carrier-aggregated counterparts.

In yet another example, one or more features of the present disclosurecan allow further segmentation of overlapping TX filters, therebyproviding, for example, significant performance improvement by loweringof insertion loss and higher isolation at both TX and RX frequencies.Such a feature can provide an important performance benefit for or whencompared to a non-carrier-aggregated system. Also, SAW technology withsimilar or better performance than FBAR technology can be utilized forbands and band combinations previously only thought possible with morecostly FBAR technology.

In yet another example, one or more features of the present disclosurecan justify additional overlapping filter segmentation that adds filtercontent for performance benefit. For example, such justification can beprovided by one filter for both of B3 TX with B4 TX, and one filter forboth of B1 RX with B4 RX.

In yet another example, one or more features of the present disclosurecan allow foregoing filter segmentation to be extended to RX filters forpotentially similar advantages. In some embodiments, both of TX and RXfilters can be segmented.

In some embodiments, a switch associated with a filter as describedherein can include an extra dedicated switch throw. Such a dedicatedthrow can be coupled to a shunt circuit configured to provide, forexample, a desirable or additional inductance/reactance as needed ordesired to match a filter combination. In some embodiments, such a shuntmatching throw can also include, for example, one or more notches foradditional harmonic filtering, and a desired impedance (e.g., 50 Ohms)for absorptive and/or shorts for isolation states.

Examples of Product Implementations:

FIG. 12 shows that in some embodiments, one or more features of thepresent disclosure can be implemented in a front-end module (FEM) 300for an RF device such as a wireless device. Such a FEM can include anassembly 302 of TX and RX filters having one or more features asdescribed herein. The FEM 300 can also include a switching circuit 304having one or more features as described herein. In some embodiments,control of the switching circuit 304 can be performed or facilitated bya controller 306. The FET 300 can be configured to be in communicationwith an antenna 308.

In some implementations, an architecture, a device and/or a circuithaving one or more features described herein can be included in an RFdevice such as a wireless device. Such an architecture, a device and/ora circuit can be implemented directly in the wireless device, in one ormore modular forms as described herein, or in some combination thereof.In some embodiments, such a wireless device can include, for example, acellular phone, a smart-phone, a hand-held wireless device with orwithout phone functionality, a wireless tablet, a wireless router, awireless access point, a wireless base station, etc.

FIG. 13 schematically depicts an example wireless device 900 having oneor more advantageous features described herein. In some embodiments,such advantageous features can be implemented in a front-end (FE) module300.

PAs in a PA module 912 can receive their respective RF signals from atransceiver 910 that can be configured and operated in known manners togenerate RF signals to be amplified and transmitted, and to processreceived signals. The transceiver 910 is shown to interact with abaseband sub-system 908 that is configured to provide conversion betweendata and/or voice signals suitable for a user and RF signals suitablefor the transceiver 910. The transceiver 910 is also shown to beconnected to a power management component 906 that is configured tomanage power for the operation of the wireless device 900. Such powermanagement can also control operations of the baseband sub-system 908and other components of the wireless device 900.

The baseband sub-system 908 is shown to be connected to a user interface902 to facilitate various input and output of voice and/or data providedto and received from the user. The baseband sub-system 908 can also beconnected to a memory 904 that is configured to store data and/orinstructions to facilitate the operation of the wireless device, and/orto provide storage of information for the user.

In the example wireless device 900, the PA module 912 can include anassembly of filters (302) configured to provide duplexing/multiplexingfunctionalities as described herein. Such filters 302 can be incommunication with an antenna switch module (ASM) 304 having one or morefeatures as described herein. In some embodiments, functionalities suchas band-selection and filtering of RF signals as described herein can beimplemented in the filters 302 and/or the ASM 304. In FIG. 13, receivedsignals are shown to be routed from the ASM 304 to one or more low-noiseamplifiers (LNAs) 918. Amplified signals from the LNAs 918 are shown tobe routed to the transceiver 910.

A number of other wireless device configurations can utilize one or morefeatures described herein. For example, a wireless device does not needto be a multi-band device. In another example, a wireless device caninclude additional antennas such as diversity antenna, and additionalconnectivity features such as Wi-Fi, Bluetooth, and GPS.

One or more features of the present disclosure can be implemented withvarious cellular frequency bands as described herein. Examples of suchbands are listed in Table 5. It will be understood that at least some ofthe bands can be divided into sub-bands. It will also be understood thatone or more features of the present disclosure can be implemented withfrequency ranges that do not have designations such as the examples ofTable 5.

TABLE 5 Tx Frequency Rx Frequency Band Mode Range (MHz) Range (MHz) B1FDD 1,920-1,980 2,110-2,170 B2 FDD 1,850-1,910 1,930-1,990 B3 FDD1,710-1,785 1,805-1,880 B4 FDD 1,710-1,755 2,110-2,155 B5 FDD 824-849869-894 B6 FDD 830-840 875-885 B7 FDD 2,500-2,570 2,620-2,690 B8 FDD880-915 925-960 B9 FDD 1,749.9-1,784.9 1,844.9-1,879.9 B10 FDD1,710-1,770 2,110-2,170 B11 FDD 1,427.9-1,447.9 1,475.9-1,495.9 B12 FDD699-716 729-746 B13 FDD 777-787 746-756 B14 FDD 788-798 758-768 B15 FDD1,900-1,920 2,600-2,620 B16 FDD 2,010-2,025 2,585-2,600 B17 FDD 704-716734-746 B18 FDD 815-830 860-875 B19 FDD 830-845 875-890 B20 FDD 832-862791-821 B21 FDD 1,447.9-1,462.9 1,495.9-1,510.9 B22 FDD 3,410-3,4903,510-3,590 B23 FDD 2,000-2,020 2,180-2,200 B24 FDD 1,626.5-1,660.51,525-1,559 B25 FDD 1,850-1,915 1,930-1,995 B26 FDD 814-849 859-894 B27FDD 807-824 852-869 B28 FDD 703-748 758-803 B29 FDD N/A 716-728 B30 FDD2,305-2,315 2,350-2,360 B31 FDD 452.5-457.5 462.5-467.5 B33 TDD1,900-1,920 1,900-1,920 B34 TDD 2,010-2,025 2,010-2,025 B35 TDD1,850-1,910 1,850-1,910 B36 TDD 1,930-1,990 1,930-1,990 B37 TDD1,910-1,930 1,910-1,930 B38 TDD 2,570-2,620 2,570-2,620 B39 TDD1,880-1,920 1,880-1,920 B40 TDD 2,300-2,400 2,300-2,400 B41 TDD2,496-2,690 2,496-2,690 B42 TDD 3,400-3,600 3,400-3,600 B43 TDD3,600-3,800 3,600-3,800 B44 TDD 703-803 703-803

For the purpose of description, it will be understood that“quadruplexer,” “quadruplexing” and the like can be utilizedinterchangeably with “quadplexer,” “quadplexing” and the like. It willalso be understood that “multiplexer,” “multiplexing” and the like mayor may not include “duplexer,” “duplexing” and the like.

Unless the context clearly requires otherwise, throughout thedescription and the claims, the words “comprise,” “comprising,” and thelike are to be construed in an inclusive sense, as opposed to anexclusive or exhaustive sense; that is to say, in the sense of“including, but not limited to.” The word “coupled”, as generally usedherein, refers to two or more elements that may be either directlyconnected, or connected by way of one or more intermediate elements.Additionally, the words “herein,” “above,” “below,” and words of similarimport, when used in this application, shall refer to this applicationas a whole and not to any particular portions of this application. Wherethe context permits, words in the above Detailed Description using thesingular or plural number may also include the plural or singular numberrespectively. The word “or” in reference to a list of two or more items,that word covers all of the following interpretations of the word: anyof the items in the list, all of the items in the list, and anycombination of the items in the list.

The above detailed description of embodiments of the invention is notintended to be exhaustive or to limit the invention to the precise formdisclosed above. While specific embodiments of, and examples for, theinvention are described above for illustrative purposes, variousequivalent modifications are possible within the scope of the invention,as those skilled in the relevant art will recognize. For example, whileprocesses or blocks are presented in a given order, alternativeembodiments may perform routines having steps, or employ systems havingblocks, in a different order, and some processes or blocks may bedeleted, moved, added, subdivided, combined, and/or modified. Each ofthese processes or blocks may be implemented in a variety of differentways. Also, while processes or blocks are at times shown as beingperformed in series, these processes or blocks may instead be performedin parallel or may be performed at different times.

The teachings of the invention provided herein can be applied to othersystems, not necessarily the system described above. The elements andacts of the various embodiments described above can be combined toprovide further embodiments.

While some embodiments of the inventions have been described, theseembodiments have been presented by way of example only and are notintended to limit the scope of the disclosure. Indeed, the novel methodsand systems described herein may be embodied in a variety of otherforms; furthermore, various omissions, substitutions and changes in theform of the methods and systems described herein may be made withoutdeparting from the spirit of the disclosure. The accompanying claims andtheir equivalents are intended to cover such forms or modifications aswould fall within the scope and spirit of the disclosure.

What is claimed is:
 1. A switched multiplexing configuration to supportcarrier aggregation, the configuration comprising: a filter assemblyincluding a first filter configured to pass a first frequency rangeassociated with a first receive frequency range of a first band; thefilter assembly also including a second filter configured to pass asecond frequency range associated with a second receive frequency rangeof the first band, the first receive frequency range different from thesecond receive frequency range; the filter assembly also including athird filter configured to pass a third frequency range associated witha transmission frequency range of a second band; and the filter assemblyalso including a fourth filter configured to pass a fourth frequencyrange associated with a receive frequency range of the second band; anda switching circuit in communication with the filter assembly and anantenna port, the switching circuit including a first switch configuredto connect the first filter to the antenna port, a second switchconfigured to connect the second filter to the antenna port, a thirdswitch configured to connect the third filter to the antenna port, and afourth switch configured to connect the fourth filter to the antennaport, the first switch, the second switch, the third switch, and thefourth switch being operated independently of each other.
 2. Theconfiguration of claim 1 wherein the first receive frequency range isexclusive of the second receive frequency range.
 3. The configuration ofclaim 1 wherein the first band includes B25 and the second band includesB4.
 4. The configuration of claim 1 wherein the filter assembly furtherincludes a fifth filter configured to pass a fifth frequency rangeassociated with a transmission frequency range of the first band and theswitching circuit further includes a fifth switch configured to connectthe fifth filter to the antenna port, the fifth switch operatedindependently of the first switch, the second switch, the third switch,and the fourth switch.
 5. The configuration of claim 4 wherein theswitching circuit opens the second switch and closes the first switch,the third switch, the fourth switch, and the fifth switch to provide afirst quadruplexed configuration.
 6. The configuration of claim 5wherein the switching circuit opens the first switch and closes thesecond switch, the third switch, the fourth switch, and the fifth switchto provide a second quadruplexed configuration.
 7. The configuration ofclaim 1 wherein the first filter and the second filter are implementedwith silicon-on-insulator technology and not thin-film bulk acousticresonator technology.
 8. The configuration of claim 1 wherein the firstfilter and the second filter reduce insertion loss for the first bandrelative to a configuration that includes a single filter for the firstand second receive frequency ranges of the first band.
 9. Theconfiguration of claim 1 wherein the third filter is further configuredto pass a fifth frequency range in addition to the third frequencyrange, the fifth frequency range associated with a transmissionfrequency of a third band.
 10. The configuration of claim 9 wherein thesecond band includes B4 and the third band includes B3.
 11. Theconfiguration of claim 1 wherein the fourth filter is further configuredto pass a fifth frequency range in addition to the fourth frequencyrange, the fifth frequency range associated with a receive frequency ofa third band.
 12. The configuration of claim 11 wherein the second bandincludes B4 and the third band includes B1.
 13. The configuration ofclaim 1 wherein the filter assembly further includes a duplexerconfigured to pass a receive frequency range associated with a thirdband and to pass a transmission frequency range associated with thethird band; and the switching circuit further includes a fifth switchconfigured to connect the duplexer to the antenna port, the fifth switchoperated independently of the first switch, the second switch, the thirdswitch, and the fourth switch.
 14. The configuration of claim 13 whereinthe third band includes B7.
 15. A radio-frequency (RF) modulecomprising: a packaging substrate configured to receive a plurality ofcomponents; a filter assembly implemented on the packaging substrate,the filter assembly including a first filter configured to pass a firstfrequency range associated with a first receive frequency range of afirst band; the filter assembly also including a second filterconfigured to pass a second frequency range associated with a secondreceive frequency range of the first band, the first receive frequencyrange different from the second receive frequency range; the filterassembly also including a third filter configured to pass a thirdfrequency range associated with a transmission frequency range of asecond band; and the filter assembly also including a fourth filterconfigured to pass a fourth frequency range associated with a receivefrequency range of the second band; and a switching circuit implementedon the packaging substrate and in communication with the filter assemblyand an antenna port, the switching circuit including a first switchconfigured to connect the first filter to the antenna port, a secondswitch configured to connect the second filter to the antenna port, athird switch configured to connect the third filter to the antenna port,and a fourth switch configured to connect the fourth filter to theantenna port, the first switch, the second switch, the third switch, andthe fourth switch being operated independently of each other.
 16. The RFmodule of claim 15 wherein the first band includes B25 and the secondband includes B4.
 17. The RF module of claim 15 wherein the filterassembly further includes a fifth filter configuration to pass a fifthfrequency range associated with a transmission frequency range of thefirst band and the switching circuit further includes a fifth switchconfigured to connect the fifth filter to the antenna port, the fifthswitch operated independently of the first switch, the second switch,the third switch, and the fourth switch.
 18. A wireless devicecomprising: a transceiver configured to process radio-frequency signals;a front-end module (FEM) in communication with the transceiver, the FEMhaving a filter assembly including a first filter configured to pass afirst frequency range associated with a first receive frequency range ofa first band; the filter assembly also including a second filterconfigured to pass a second frequency range associated with a secondreceive frequency range of the first band, the first receive frequencyrange different from the second receive frequency range; the filterassembly also including a third filter configured to pass a thirdfrequency range associated with a transmission frequency range of asecond band; and the filter assembly also including a fourth filterconfigured to pass a fourth frequency range associated with a receivefrequency range of the second band; the FEM also having a switchingcircuit in communication with the filter assembly and an antenna port,the switching circuit including a first switch configured to connect thefirst filter to the antenna port, a second switch configured to connectthe second filter to the antenna port, a third switch configured toconnect the third filter to the antenna port, and a fourth switchconfigured to connect the fourth filter to the antenna port, the firstswitch, the second switch, the third switch, and the fourth switch beingoperated independently of each other; and an antenna in communicationwith the antenna port, the antenna configured to facilitate either orboth of transmission and receiving of radio-frequency signals.
 19. Thewireless device of claim 18 wherein the first band includes B25 and thesecond band includes B4.
 20. The wireless device of claim 18 wherein thefilter assembly further includes a fifth filter configured to pass afifth frequency range associated with a transmission frequency range ofthe first band and the switching circuit further includes a fifth switchconfigured to connect the fifth filter to the antenna port, the fifthswitch operated independently of the first switch, the second switch,the third switch, and the fourth switch.